Kristen Stewart and Taylor Lautner attended a concert together at The Troubadour in LA last night. Kristen and Taylor dropped by the venue with a group of friends — including Katy Perry's assistant, Tamra Natisin, whom Kristen hit the town with on Sunday — to see Marcus Foster perform. Marcus has been a longtime friend of Kristen's and she even starred in his "I Was Broken" music video back in 2011. Noticeably absent from the bunch was Robert Pattinson, who is currently filming The Rover in Australia. Rob is also close with Marcus, and even sang the musician's song "Let Me Sign" for the Twilight soundtrack back in 2008.